Parent command

Extended description

Login to a self-hosted registry

If you want to login to a self-hosted registry you can specify this by
adding the server name.

$ docker login localhost:8080

Provide a password using STDIN

To run the docker login command non-interactively, you can set the
--password-stdin flag to provide a password through STDIN. Using
STDIN prevents the password from ending up in the shell’s history,
or log-files.

The following example reads a password from a file, and passes it to the
docker login command using STDIN:

Privileged user requirement

connecting to a remote daemon, such as a docker-machine provisioned docker engine.

user is added to the docker group. This will impact the security of your system; the docker group is root equivalent. See Docker Daemon Attack Surface for details.

You can log into any public or private repository for which you have
credentials. When you log in, the command stores credentials in
$HOME/.docker/config.json on Linux or %USERPROFILE%/.docker/config.json on
Windows, via the procedure described below.

Credentials store

The Docker Engine can keep user credentials in an external credentials store,
such as the native keychain of the operating system. Using an external store
is more secure than storing credentials in the Docker configuration file.

To use a credentials store, you need an external helper program to interact
with a specific keychain or external store. Docker requires the helper
program to be in the client’s host $PATH.

This is the list of currently available credentials helpers and where
you can download them from:

You need to specify the credentials store in $HOME/.docker/config.json
to tell the docker engine to use it. The value of the config property should be
the suffix of the program to use (i.e. everything after docker-credential-).
For example, to use docker-credential-osxkeychain:

{"credsStore":"osxkeychain"}

If you are currently logged in, run docker logout to remove
the credentials from the file and run docker login again.

Default behavior

By default, Docker looks for the native binary on each of the platforms, i.e.
“osxkeychain” on macOS, “wincred” on windows, and “pass” on Linux. A special
case is that on Linux, Docker will fall back to the “secretservice” binary if
it cannot find the “pass” binary. If none of these binaries are present, it
stores the credentials (i.e. password) in base64 encoding in the config files
described above.

Credential helper protocol

Credential helpers can be any program or script that follows a very simple protocol.
This protocol is heavily inspired by Git, but it differs in the information shared.

The helpers always use the first argument in the command to identify the action.
There are only three possible values for that argument: store, get, and erase.

The store command takes a JSON payload from the standard input. That payload carries
the server address, to identify the credential, the user name, and either a password
or an identity token.

If the secret being stored is an identity token, the Username should be set to
<token>.

The store command can write error messages to STDOUT that the docker engine
will show if there was an issue.

The get command takes a string payload from the standard input. That payload carries
the server address that the docker engine needs credentials for. This is
an example of that payload: https://index.docker.io/v1.

The get command writes a JSON payload to STDOUT. Docker reads the user name
and password from this payload:

{"Username":"david","Secret":"passw0rd1"}

The erase command takes a string payload from STDIN. That payload carries
the server address that the docker engine wants to remove credentials for. This is
an example of that payload: https://index.docker.io/v1.

The erase command can write error messages to STDOUT that the docker engine
will show if there was an issue.

Credential helpers

Credential helpers are similar to the credential store above, but act as the
designated programs to handle credentials for specific registries. The default
credential store (credsStore or the config file itself) will not be used for
operations concerning credentials of the specified registries.

Logging out

If you are currently logged in, run docker logout to remove
the credentials from the default store.

Credential helpers are specified in a similar way to credsStore, but
allow for multiple helpers to be configured at a time. Keys specify the
registry domain, and values specify the suffix of the program to use
(i.e. everything after docker-credential-).
For example: